#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b;
	double m=0;
	cin>>a;
	if(a>=401)
	{
		b=a-400;
		m+=b*0.85;
		a-=b;
	}
	if(151<=a&&a<=400)
	{
		b=a-150;
		m+=b*0.766;
		a-=b;
	}
	if(a<=150)
	m+=a*0.565;
	printf("%.1f",m);
    return 0;
}

